//作业一：
const task = (str) => {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve(str);
    }, 10);
  });
};

task('hello ')
  .then((res) => {
    return task(res + 'lagou ');
  })
  .then((res) => {
    return task(res + 'I ♥ U');
  })
  .then((res) => {
    console.log(res);
  });

//please make node taskOne.js to run this task;
